package main

import "fmt"

func doubleOrNothing(n int) int {
	return 0
}

var _ func(int) int = doubleOrNothing

func main() {
	for _, t := range []struct {
		in, want int
	}{
		{1, 2},
		{-1, 0},
		{0, 0},
		{42, 84},
		{-42, 0},
	} {
		if g := doubleOrNothing(t.in); g != t.want {
			fmt.Printf("doubleOrNothing(%v) = %v, want %v\n", t.in, g, t.want)
			fmt.Println("Try again!")
			return
		}
	}
	fmt.Println("PASS")
}

/*
func doubleOrNothing(n int) int {
	if n > 0 {
		return n * 2
	}
	return 0
}
*/
